What is Cardinality, and how do you find it for a column? This simple script shows the percentage of unique values, using an AdventureWorks table.
Find Memory Used by Each Database in SQL Server
To see the memory used by each database, count its pages in the buffer pool with sys.dm_os_buffer_descriptors. This post builds a small demo database, shows buffer and dirty page sizes before and after a checkpoint, explains the row with no name, and covers what the buffer pool numbers leave out, such as the plan cache.
SQL SERVER – Install Error: Microsoft Cluster Service (MSCS) Cluster Verification Errors – Part 3
Part 3: one more reason SQL Server setup can fail the MSCS cluster verification errors rule during install or AddNode, as seen at a client, and the fix.
SQL SERVER – How to Know Transaction Isolation Level for Each Session?
An outsourced app had teams using different coding standards, and performance suffered. Here is how to find the transaction isolation level of each session.
Integration Services Evaluation Period Has Expired: Maintenance Plan Fails
The Integration Services evaluation period can expire while the Database Engine keeps running, and the maintenance plan that depends on it fails. In one client case backups stopped. These checks show how to find the failure, close the backup gap and identify the expiring component.
The Tipping Point: Why SQL Server Skips Your Nonclustered Index
Find the tipping point where key lookups cost more than a scan, then compare covering and filtered indexes with measured reads.
Linting T-SQL: Rules Worth Automating in a Build
Use linting T-SQL to flag repeatable code risks, review catalog-based candidates, and automate confirmed rules without false certainty.